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    Covid-19 Vaccine Acceptance and Risk Perception in Ghana: Insights from A Study on Tertiary-Level Students and Surrounding Residents in Kumasi
    (Journal of Science and Technology, 2024) Darko, Samuel Nkansah; Boahen, Kennedy Gyau; Okyere, Portia Boakye; Addo, Christopher N. K.; Ameyaw, Afuaa Janet; Adjei, Emmanuel; Hayford, Manuella; Anhwere, Naomi Efua; Kwarteng, Sandra Abankwa
    The introduction of COVID-19 vaccines in sub-Saharan Africa has been met with mixed feelings. In Ghana, several concerns were raised about the potency and side effects of the COVID-19 vaccine. We investigated the acceptance and risk perception of students on the KNUST campus and the residents of the surrounding communities to assess the risk factors that will influence heir willingness or unwillingness to be vaccinated in the government’s quest to get its citizens vaccinated. A well-structured questionnaire was administered online and through face-toface interviews to survey 3332 respondents between the periods of March 15 and May 28, 2021. Chi-square analysis was used to show the association between the sociodemographic characteristics and, the acceptance and risk perception of the COVID-19 vaccine. Logistic regression analysis was used to explain the relationship between the acceptance and risk perception of the COVID-19 vaccine and the various socio-demographic characteristics. Out of 3323 respondents, 1,703 (45.23%) were hesitant whiles 64.39% of 3311 indicated they would accept being vaccinated. In a multivariate analysis, the age range of 31 to 40 years, being male, having secondary level education, and having a previous vaccination post-childhood immunization increased the likelihood of vaccine acceptance. More than half of the students of KNUST and inhabitants around the campus are likely to acceptant the COVID-19 vaccine. However, adequate and timely information is needed to educate prospective vaccine recipients with tertiary level education to better the level of acceptance and address misinformation about vaccines and promote individual and population-level benefits of vaccination
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    Cutting resistance assessment for three varieties of cassava roots
    (Journal of the Ghana Institution of Engineering, 2023-11-27) Amoah, Francis; Asante, Eric Amoah; Amuaku, Randy; Bobobee, Emmanuel Yaovi Hunnuor
    In this study, a model has been developed to assess the peel and root resistance to cutting. The evaluation was done with knife thicknesses of 1.0 mm, 1.5 mm and 2.0 mm using Duade kpakpa, Dudze and Sika bankye cassava varieties as experimental samples for three postharvest delays. The knife penetrated the tuber at 50 mm, 100 mm and 150 mm away from the proximal end. An average peel thickness obtained was in the range of 1.81 mm – 3.01 mm. The average diameters recorded ranged from 52.52 mm to 60.40 mm. The cutting resistance assessed for the Duade kpakpa, Sika bankye and Dudze cassava peels were 44.85 N, 50.01 N and 53.53 N, respectively with no significant differences (p < 0.05). The penetration resistance of the tuber decreased with increasing postharvest delay and increased with increasing knife thickness. The effect of the treatments on the response variables evaluated by factorial analysis showed that significant differences generally decrease with increasing interaction. Comparing the results, cutting resistances of 229.02 N, 223.09 N and 204.43 N in maximum were obtained for the Dudze, Sika bankye and Duade kpakpa cassava roots, respectively. The quantitative assessment by the PLSR model under the knife thicknesses (R2 = 0.9689; RMSE = 2.1020) was significantly better than the PLSR model under postharvest delay (R2 = 0.7845; RMSE = 4.0183). The technique employed in assessing the cutting resistance emphasized the cultivar differences and provided a measuring sequence and outstanding quantitative analysis.
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    Development and evaluation of agro-waste composite for sound insulation
    (Journal of the Ghana Institution of Engineering, 2023-11-30) Amuaku, Randy; Amanor, Godwin K.; Adu-Gyamfi, Fehrs; Asante, Eric Amoah; Kweitsu, Eric; Opare, Samuel
    The palm kernel shell is a by-product of palm kernel oil production and is commonly used in the natural biomass energy industry. Coconut husk fibre is extracted from the coconut fruit. To find a use for palm kernel shells and coconut husk fibre, a composite insulator plate was developed by the addition of a binder through a process of grinding, sieving, mixing, heating, hot-pressing and cooling in a mould. An Ahuja speaker AU60 was fixed at one end of a baffled tube and a sound level meter was placed 2 m away from the output to record sound transmission loss at 5s intervals for twenty minutes. The plates of 3, 4, 5, and, 6 mm thickness were fixed in the baffled tube at a distance of 475 mm away from the input one after the other to filter the input sound. The results showed that the setup without a composite insulator recorded the highest noise of 226.8 dB. The average recorded sound transmitted loss was 185.40, 72.47, 74.54, 76.06, and 82.85 dB for no insulator, 3, 4, 5 and, 6 mm composite insulators respectively. The introduction of the 3, 4, 5, and, 6 mm thickness composite insulators resulted in 55.3 %, 59.0 %, 59.8 % and 60.9 % reduction in noise level. The application of agro-waste composite material as a sound insulator in a baffled tube has proven to be effective by 58.7 % on average. The study has confirmed that agro-waste materials can be used in sound insulation applications.
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    Stochastic Optimal Selection and Analysis of Allowable Photovoltaic Penetration Level for Grid-Connected Systems Using a Hybrid NSGAII-MOPSO and Monte Carlo Method
    (International Journal of Photoenergy, 2023) Abubakar, Ali; Borkor, Reindorf Nartey; Amoako-Yirenkyi, Peter; 0000-0002-5721-4638
    Generally, the main focus of the grid-linked photovoltaic systems is to scale up the photovoltaic penetration level to ensure full electricity consumption coverage. However, due to the stochasticity and nondispatchable nature of its generation, significant adverse impacts such as power overloading, voltage, harmonics, current, and frequency instabilities on the utility grid arise. These impacts vary in severity as a function of the degree of penetration level of the photovoltaic system. Thus, the design problem involves optimizing the two conflicting objectives in the presence of uncertainty without violating the grid’s operational limitations. Nevertheless, existing studies avoid the technical impact and scalarize the conflicting stochastic objectives into a single stochastic objective to lessen the degree of complexity of the problem. This study proposes a stochastic multiobjective methodology to decide on the optimum allowable photovoltaic penetration level for an electricity grid system at an optimum cost without violating the system’s operational constraints. Five cutting-edge multiobjective optimization algorithms were implemented and compared using hypervolume metric, execution time, and nonparametric statistical analysis to obtain a quality solution. The results indicated that a Hybrid NSGAII-MOPSO had better convergence, diversity, and execution time capacity to handle the complex problem. The analysis of the obtained optimal solution shows that a practical design methodology could accurately decide the maximum allowable photovoltaic penetration level to match up the energy demand of any grid-linked system at a minimum cost without collapsing the grid’s operational limitations even under fluctuating weather conditions. Comparatively, the stochastic approach enables the development of a more sustainable and affordable grid-connected system.
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    3-Monochloropropandiol and glycidyl esters in heat-processed oil-based food products: Exposure and risk
    (Applied Food Research, 2024-06) Yabani, Daniel Sitsofe; Ofosu, Isaac Williams; Ankar-Brewoo, Gloria Mathanda; Lutterodt, Herman Erick; 0000-0001-5442-6654; 0000-0002-9553-0834; 0000-0001-8574-3409; 0000-0001-7015-7597
    Fatty acid esters of 3-monochloro-1,2-propanediol (3-MCPDE) and glycidol (GE) are potentially harmful heatinduced contaminants produced during food processing. In this study, 100 heat-treated oil-based food samples covering fried, smoked, grilled, and baked food groups were collected in Koforidua, Ghana and analysed for the two esters using gas chromatography-mass spectrometry. The dietary exposures were estimated by a probabilistic approach using Monte Carlo Simulation. Levels of 3-MCPDE and GE in the foods ranged from